Lochinvar SYNC User manual

HIGH EFFICIENCY COMMERCIAL BOILERS
www.Lochinvar.com
DESIGNER’S GUIDE SYNC COMMERCIAL BOILER
Up to 98%
Thermal Efficiency

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Designer’s Guide / SYNC Boiler
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Table of Contents
Combustion & Ventilation Air …………………… Page 2
Venting ….…………………………………………….. Page 5
Gas ….….…………….……………….………………… Page 13
Water …..……………………..……………………….. Page 15
Electricity & Controls ……………………………….. Page 21
Other Details ..……………………………………….. Page 26
Appendix A ….……..…………………………………. Page 29
Appendix B …………………………………………… Page 34
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Designer’s Guide / SYNC Boiler
At Lochinvar, we know that designing a boiler is hard work. Designing a boiler system is
no picnic either. Demands for greater efficiency and elaborate system control have
made systems more complex.
This designers guide will break down the system requirements that match the SYNC
boiler to assure safe operation, highly efficient heating and long life.
There are five major elements of boiler system design:
Combustion &
Ventilation Air
(See page 2)
Venting
(See page 5)
Gas
(See page 13)
Water
(See page 15)
Electricity &
Controls
(See page 21)
Plus many other important details:
Locations Suggested Piping Diagrams
(See page 27 for “Location of Unit”) (See Appendix “A”)
High Altitude Requirements Component List
(See page 28 for “High Altitude Applications”) (See Appendix “B”)
Gas
Water
Electricity&
Controls
Combustion
&
Ventilation
Air
Venting

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Designer’s Guide / SYNC Boiler
Chapter 1 – Combustion and
Ventilation Air
The first, important design consideration is air. Everybody’s gotta breathe. Even boilers need air.
Air seems easy enough. You stand in the equipment room and you breathe comfortably, don’t
you? Open a door. Open a window. This is a big room. There’s lots of air in here for the boiler,
right?
The average person inhales 400 to 500 cubic feet of air in a 24 hour period. A one million Btu/hr
boiler will draw 226.38 cubic feet of air every MINUTE! A 20 by 20 by 8 foot equipment room
holds 3200 cubic feet of air. That’s a volume of air to last you or me over six days. A one million
Btu/hr SYNC will consume 3200 cubic feet of air in 14 minutes.
Therefore, a good, easy flow of clean air is 100% necessary for clean, efficient combustion. So,
we need to provide a permanent and uninterrupted flow of air to the boiler. The SYNC boiler is
designed to receive combustion air by one of TWO methods. The boiler may draw combustion
air from the room or have the air ducted directly to the boiler from an exterior space.
This chapter explains the methods for “air from the room”. Chapter 2 explains “air ducted directly
to the boiler”. Again, this chapter lists several techniques to size the air openings that will deliver
room air. If there are other appliances in the room requiring air, their air requirements must be
including when sizing the air openings.
Provisions for combustion and ventilation air must be
designed and installed in accordance with “Air for
Combustion and Ventilation”, of the latest edition of the
National Fuel Gas Code, ANSI Z223.1, (in Canada, the
latest edition of CGA Standard B149 Installation Code for
Gas Burning Appliances and Equipment) or applicable
provisions of the local building codes.
NEGATIVE PRESSURE IN THE EQUIPMENT ROOM
It is important to NEVER have a negative pressure on the equipment room. Exhaust fans are
popular in equipment rooms to exchange the air. If the exhaust fan pulls air OUT, then a negative
pressure occurs in the room. The combustion and ventilation air must be sized to supply all the
equipment PLUS the air for the exhaust fan.
COMBUSTION AND VENTILATION AIR SIZING CALCULATIONS
The sizing calculations in this section are based on “Free Area”. The
louvers or grill used on the air openings must have a net free area equal
to or greater than the value derived in the calculations. The Free Area in
a louver or grill is defined as the open, unblocked area. The louvers,
grills, mesh, blades, all will block a given amount of space in the louver’s
overall dimension. Consult the louver manufacturer for exact net free
area of the louver.
A
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Designer’s Guide / SYNC Boiler
1. COMBUSTION AIR FROM OUTSIDE
If air is taken directly from outside the building with no
duct, provide two permanent openings to the
equipment room:
(a) Combustion air opening, with a minimum free area
of one square inch per 4000 Btu/hr input (5.5 cm²
per
kW). This opening must be located within 12" (30 cm)
of the bottom of the enclosure.
(b) Ventilation air opening, with a minimum free area of
one square inch per 4000 Btu/hr input (5.5 cm²
per
kW). This opening must be located within 12" (30 cm)
of the top of the enclosure.
2. COMBUSTION AIR THROUGH DUCTS
If combustion and ventilation air is taken from the outdoors using
a duct to deliver the air to the equipment room, each of the two
openings should be sized based on a minimum free area of one
square inch per 2000 Btu/hr (11 cm²
per kW) of input.
3. COMBUSTION AIR FROM INTERIOR
SPACE
If air is taken from another interior space,
each of the two openings specified above
should have a net free area of one square
inch for each 1000 Btu/hr (22 cm²
per kW) of
input, but not less than 100 square inches
(645 cm²).
THE SYNC COMES WITH LOUVER CONTACTS AS STANDARD EQUIPMENT. THE CONTACTS WILL
OPEN AND CLOSE A MOTORIZED LOUVER ON EACH CALL FOR HEAT.
Did you Know?

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Designer’s Guide / SYNC Boiler
4. DIRECT OUTSIDE AIR, SINGLE OPENING
If a single combustion air opening is provided to bring
combustion air in directly from the outdoors, the opening
must be sized based on a minimum free area of one
square inch per 3000 Btu/hr (7 cm²
per kW). This opening
must be located within 12" (30 cm) of the top of the
enclosure.
The combustion air must be free of any contaminants or chemical fumes. Salts, refrigerants and
solvents introduced into the combustion process will result in the formation of corrosive acids that
will damage the appliance and the vent.

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Designer’s Guide / SYNC Boiler
Chapter 2 – Venting
Venting is another important design element for the installation of a gas fired appliance. It has a
variety of choices, many different vent configurations to chose from, rules and regulations that
govern the installation and most important of all, it bears a requirement for human safety.
Lochinvar offers five different vent configurations on the SYNC boiler to meet the building’s
requirements. They are…
Vertical Vent with Air from the Equipment Room
Vertical Vent with Air from the Rooftop
Vertical Vent with Air from the Sidewall
Sidewall Vent with Air from the Equipment Room
Sidewall Vent with Air from the Sidewall
Part 1
Vent Categories
Lochinvar offers five venting options with the SYNC that must be installed with approved
Category IV vent material. Below is the vent category diagram, standard throughout the industry.
The four basic Vent Categories are determined by two characterisitics, Condensation and
Pressure.
In all vent configurations, the SYNC boiler will operate in Category IV. The modulation of the
burner down to 10% of the boiler’s input will put low temperature flue products in the stack that
will condense. The boiler’s blowers are designed to push the flue products through the exhaust
system with a consistent positive pressure.
Always use Category IV approved non-corrosive vent material and always seal the joints and
connections 100% gas tight in order to prevent condensation and flue gas leakage.
CATEGORY I
Non‐Condensing
Non‐PositivePressure
CATEGORY III
Non‐Condensing
PositivePressure
CATEGORY II
Condensing
Non‐PositivePressure
CATEGORY IV
Condensing
PositivePressure
SPILLAGE OF FLUE PRODUCTS AND CARBON MONOXIDE EMISSIONS PRODUCED BY THE
COMBUSTION PROCESS CAN CAUSE SEVERE PERSONAL INJURY OR DEATH.
Warning
Venting

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Designer’s Guide / SYNC Boiler
VERTICAL VENT WITH COMBUSTION AIR FROM EQUIPMENT ROOM.
The flue outlet terminates on the rooftop. The combustion air is drawn
from the equipment room.
BULLET POINTS
Category IV vent material is required, such as AL29-4C or PVC/CPVC.
All vent joints and seams must be sealed gastight and may not be common vented.
All vent material for this configuration including vent termination will be obtained locally.
The air is delivered to the equipment room by means defined in Chapter 1 of this
designer’s guide.
When venting with PVC, the first ten feet of pipe must be CPVC for heat protection. See
page 12 of the installation manual for details.
 VENTVENTVENT
MODELDIAMETERMIN.LENGTHMAX.LENGTH
SBN10006"12ft100ft
SBN13006"12ft100ft
SBN15006"12ft100ft
A 90° VENT ELBOW IS EQUAL TO 5 LINIER FEET OF VENT PIPE AND ALL VENT ELBOWS MUST BE
ACCOUNTED FOR IN THE TOTAL VENT LENGTH. SEE SYNC I & O MANUAL FOR DETAILS.
Did you Know?

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Designer’s Guide / SYNC Boiler
SIDEWALL VENT WITH COMBUSTION AIR FROM EQUIPMENT ROOM.
The flue outlet terminates out the sidewall. The combustion air is drawn
from the equipment room.
BULLET POINTS
Category IV vent material is required, such as AL29-4C or PVC/CPVC.
All vent joints and seams must be sealed gastight and may not be common vented.
All vent material for this configuration including vent termination will be obtained locally.
The sidewall termination plate may be used with PVC or CPVC vent material.
The air is delivered to the equipment room by means defined in Chapter 1 of this
designer’s guide.
When venting with PVC, the first ten feet of pipe must be CPVC for heat protection. See
page 12 of the installation manual for details.
 VENTVENTVENT
MODELDIAMETERMIN.LENGTHMAX.LENGTH
SBN10006"12ft100ft
SBN13006"12ft100ft
SBN15006"12ft100ft

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Designer’s Guide / SYNC Boiler
VERTICAL VENT WITH COMBUSTION AIR FROM THE ROOFTOP.
The flue outlet terminates on the rooftop. The combustion air is ducted to
the appliance from outdoors through the rooftop. This is true Direct Vent
with the flue termination and the air inlet port in the same pressure zone.
BULLET POINTS
Category IV vent material is required, such as AL29-4C or PVC/CPVC.
All vent joints and seams must be sealed gastight and may not be common vented.
All other vent material for this configuration including vent termination will be obtained
locally.
The air is delivered to the appliance via a separate duct. The air intake material can be
galvanized pipe, PVC, CPVC or ABS and must be sealed gas tight.
When venting with PVC, the first ten feet of pipe must be CPVC for heat protection. See
page 12 of the installation manual for details.
 AIRINTAKEAIRINTAKEAIRINTAKEVENTVENTVENT
MODELDIAMETERMIN.LENGTHMAX.LENGTHDIAMETERMIN.LENGTHMAX.LENGTH
SBN10006"12ft100ft6"12ft100ft
SBN13006"12ft50ft6"12ft50ft
SBN13007"12ft100ft7"12ft100ft
SBN15006"12ft50ft6"12ft50ft
SBN15007"12ft100ft7"12ft100ft

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Designer’s Guide / SYNC Boiler
SIDEWALL VENT WITH COMBUSTION AIR FROM THE SIDEWALL.
The flue outlet terminates on the sidewall. The combustion air is ducted to
the appliance from outdoors through the sidewall. This is true Direct Vent
with the flue termination and the air inlet port in the same pressure zone.
BULLET POINTS
Category IV vent material is required, such as AL29-4C or PVC/CPVC.
All vent joints and seams must be sealed gastight and may not be common vented.
All other vent material for this configuration will be obtained locally.
The vent termination plate for PVC/CPVC venting is supplied with the boiler.
The vent termination plate for Stainless Steel venting is an optional kit available through
Lochinvar. The kit part numbers are KIT30028 for 6” termination and KIT30029 for 7”
termination.
The air is delivered to the appliance via a separate duct. The air intake material can be
galvanized pipe, PVC, CPVC or ABS and must be sealed gas tight.
When venting with PVC, the first ten feet of pipe must be CPVC for heat protection. See
page 12 of the installation manual for details.
 AIRINTAKEAIRINTAKEAIRINTAKEVENTVENTVENT
MODELDIAMETERMIN.LENGTHMAX.LENGTHDIAMETERMIN.LENGTHMAX.LENGTH
SBN10006"12ft100ft6"12ft100ft
SBN13006"12ft50ft6"12ft50ft
SBN13007"12ft100ft7"12ft100ft
SBN15006"12ft50ft6"12ft50ft
SBN15007"12ft100ft7"12ft100ft

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Designer’s Guide / SYNC Boiler
VERTICAL VENT WITH COMBUSTION AIR FROM THE SIDEWALL.
The flue outlet terminates on the rooftop. The combustion air is ducted to
the appliance from outdoors through the sidewall. This is NOT true Direct
Vent where the flue termination and the air inlet port are in the same
pressure zone.
BULLET POINTS
Category IV vent material is required, such as AL29-4C or PVC/CPVC.
All vent joints and seams must be sealed gastight and may not be common vented.
All other vent material for this configuration will be obtained locally.
The vent termination plate for PVC/CPVC venting is supplied with the boiler.
The vent termination plate for Stainless Steel venting is an optional kit available through
Lochinvar.
The air is delivered to the appliance via a separate duct. The air intake material can be
galvanized pipe, PVC, CPVC or ABS and must be sealed gas tight.
When venting with PVC, the first ten feet of pipe must be CPVC for heat protection. See
page 12 of the installation manual for details.
 AIRINTAKEAIRINTAKEAIRINTAKEVENTVENTVENT
MODELDIAMETERMIN.LENGTHMAX.LENGTHDIAMETERMIN.LENGTHMAX.LENGTH
SBN10006"12ft100ft6"12ft100ft
SBN13006"12ft50ft6"12ft50ft
SBN13007"12ft100ft7"12ft100ft
SBN15006"12ft50ft6"12ft50ft
SBN15007"12ft100ft7"12ft100ft

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Designer’s Guide / SYNC Boiler
VENT TERMINATIONS, SIDEWALL AND ROOFTOP
The flue outlet and the air intake pipe may terminate out the sidewall or the rooftop in the patterns
shown on pages 6 through 10. Approved vent terminations are shown below.
The most popular method for a new installation is sidewall venting. The Vent Termination Plate
and Vent Termination Cap seen in the illustration are supplied with every SYNC boiler as
standard equipment.
Prior to the development of the Vent Termination plates, PVC and CPVC sidewall venting was
accomplished with basic and locally acquired plastic fittings. This configuration is known as
“Snorkel piping” or “Elephant Trunk piping.” For aesthetic purposes the elbows on the exhaust
pipe are installed inside the building. If space is not available, the elbows may be installed
outside the building. Even though the SYNC boiler is supplying Vent Termination Plates with
every model, Snorkel pipe terminations are approved and acceptable.
READ THE INSTALLATION AND OPERATION MANUAL FOR SPECIFIC RULES GOVERNING SIDEWALL
AND ROOFTOP TERMINATION WHICH INCLUDE LOCATIONS AND CLEARANCES FOR SINGLE AND
MULTPLE APPLIANCES.
I
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Designer’s Guide / SYNC Boiler
Vertical vent and air intake termination is also approved for the SYNC boiler. The exhaust and air
intake terminations may be installed 12” apart minimum side by side or with the air intake below
the exhaust maintaining a 12” seperation. Never install the air intake above the exhaust in either
rooftop or sidewall termination.
Due to the potential for high exhaust temperatures in the event of high water temperatures in the
system, the SYNC requires the installation of CPVC pipe for the first 10 feet of exhaust pipe. This
may be accomplished with 10 straight feet of CPVC pipe or with one 90° CPVC elbow and 5
straight feet of CPVC pipe. Do not install two 90° elbows. The sharp changes in flow direction
cause a restriction in the pipe that exceeds the equivalent length in vent material.

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Designer’s Guide / SYNC Boiler
Chapter 3 – Gas Supply
Lochinvar products are designed with the concept of flame control. We develop combustion
systems that tightly control the flow of air and gas to deliver a clean and efficient burn. In
Chapters 1 and 2, we showed the various methods to deliver an ample quantity of air to the
appliance. In Chapter 3, we discuss delivering a steady and reliable supply of gas to the
appliance.
The key to the gas supply is sizing the gas line properly from the meter to the boiler. The SYNC
will require less than a half a pound of pressure. The following Sizing Chart is based on less than
½ pound of pressure or less than 14 inches of water column. The table is derived from the ANSI
Z223.1, the National Fuel Gas Code.
Simply calculate the total linear feet of straight gas pipe. Figure each elbow as equal to five
straight feet of pipe. Working down the column that matches your pipe length, find the value
GREATER THAN the total Btu/hr input of the boiler or boilers. This will identify the minimum
nominal iron pipe size.
GAS PIPE SIZING CHART
Nominal
Iron Length of Pipe in Straight Feet
Pipe
Size 10 20 30 40 50 60 70 80 90 100 125 150 175 200
3/4" 369 256 205 174 155 141 128 121 113 106 95 86 79 74
1" 697 477 384 328 292 267 246 256 210 200 179 164 149 138
1 1/4" 1,400 974 789 677 595 543 502 472 441 410 369 333 308 287
1 1/2" 2,150 1,500 1,210 1,020 923 830 769 707 666 636 564 513 472 441
2" 4,100 2,820 2,260 1,950 1,720 1,560 1,440 1,330 1,250 1,180 1,100 974 871 820
2 1/2" 6,460 4,460 3,610 3,100 2,720 2,460 2,310 2,100 2,000 1,900 1,700 1,540 1,400 1,300
3" 11,200 7,900 6,400 5,400 4,870 4,410 4,000 3,800 3,540 3,300 3,000 2,720 2,500 2,340
4" 23,500 16,100 13,100 11,100 10,000 9,000 8,300 7,690 7,380 6,870 6,150 5,640 5,130 4,720
The SYNC features a Negative-Regulation or Neg-Reg gas combustion system. The gas is
introduced upstream of the combustion blower. As the blower draws air in, the negative pressure
on the inlet of the blower pulls the gas from the gas valve. The gas/air mixture is pushed through
the blower into the burner. The gas/air mixture filters through the micro-metal fiber burner mesh
and is ignited by the spark Igniter.
On full fire, a mostly blue flame rises off the surface of the burner.
As demand decreases, the operating control reduces the blower
speed and the gas follows the air in proportion. The flame is
reduced and touches the burner surface. The micro metal fiber
burner material is designed to burn infra-red safely without being
damaged by direct contact of the flame. Even at this reduced
Btu/hr input, the gas/air mixture is balanced to provide clean,
efficient combustion.
Gas

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Designer’s Guide / SYNC Boiler
The SYNC features an 1-1/2” gas connection. The gas pipe size from the meter to the boiler may
be larger than the appliance connection and must be properly calculated using the chart below.
In some cases, a gas pressure regulator will be required to reduce the supply pressure to the
boiler. The table below lists the Minimum and Maximum Inlet Gas Pressures.
INLET GAS PRESSURE
Model Firing NATURAL GAS L.P. GAS
Number Code Max. w.c. Min. w.c. Max. w.c. Min. w.c.
SBN1000 M13 14.0 5.0 14.0 8.0
SBN1300 M13 14.0 4.0 14.0 8.0
SBN1500 M13 14.0 4.0 14.0 8.0
L.P. GAS MODELS
If you require a model for connection to L.P. gas, make sure that is noted on your design
specification. Example, the model number changes from SBN1500 to SBL1500 from natural to
L.P. gas. The SYNC must be factory trimmed for the chosen gas type and may not be field
converted from Natural to L.P. gas or from L.P. to Natural gas.
GAS PRESSURE REGULATORS
Lochinvar recommends the use of “Lock-Up Type” gas pressure regulators on the system gas
supply. A Lock-Up Type gas pressure regulator features a seat that seals the regulator orifice
when the appliance is off and there is no demand for gas. The seat will seal against the orifice
shutting off the flow of gas to the appliance.
A standard regulator without a Lock-Up mechanism will allow the system pressure to reach the
boiler when it is off. The system pressure can “creep up” pressing against the appliance gas train
with excessive system pressures. This can damage the components in the gas train.
HIGH PRESSURE GAS REGULATORS MUST BE THE LOCK-UP VARIETY AND MUST BE INSTALLED NOT
LESS THAN 10 EQUIVALENT FEET FROM THE BOILER TO PROVIDE AN ADEQUATE VOLUME OF GAS
FOR SMOOTH IGNITION.
I
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Designer’s Guide / SYNC Boiler
Chapter 4 – Water
Water flow, water temperature and water volume in modern hydronic heating systems are all
elements of system design that need to be carefully planned. Today’s high efficiency, low-mass
heating boilers require a closer look at these design parameters in order to maximize the
efficiency and the life of the appliance.
There are three major concepts to consider when
designing the near boiler piping system. They are…
WATER FLOW
WATER TEMPERATURE
WATER VOLUME
A boiler or bank of boilers has a given range of operation under these three concepts. A boiler
has a water flow rate range, a water temperature range and a water volume range. If you design
a system that lets the boiler operate within its comfort zone, it performs efficiently and will have a
good life expectancy. If the system forces the boiler to operate outside any one of the three
comfort zones; the boiler suffers.
WATER FLOW
Minimum and maximum Flow Rates must be maintained per the design parameters of the boiler.
Does the maximum planned flow rate for the system loop exceed the maximum
allowable flow rate through the boiler?
The maximum flow rate for the SYNC 1000-1500 models is 90 GPM per heat
exchanger.
IMPORTANT BULLET POINTS FOR WATER PIPING
1. Water Connections
All models have two 2 inch black iron NPT inlet connections and one 2-1/2 inch black
iron NPT outlet connection. Installed piping to and from the boiler must be a minimum
of 2-1/2 inch diameter.
2. Maximum Flow Rate
The SYNC models have a max flow rate of 90 GPM per heat exchanger.
3. Working Pressure
The boiler should not be operated at less than 12 PSIG.
4. Minimum Inlet Water Temperature
The minimum inlet water temperature returned to the boiler is 40°F (4.44°C).
5. Flow Rate
The boiler requires a constant flow rate through each heat exchanger. Do not vary the
flow rate through the boiler during a call for heat.
6. Unions and Ball Valves
The water piping to the boiler should have unions and ball valves at the inlet and outlet
of the boiler to isolate the boiler for service. Use only full port ball valves.
Water

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Designer’s Guide / SYNC Boiler
Because system flow rates and boiler flow rates need to be controlled separately, you will want to
design a Primary / Secondary piping loop. The Primary Loop, hereafter referred to as the
“System Loop” flows water around the building and delivers heat to the building. The Secondary
Loop, hereafter referred to as the “Boiler Loop” branches off the system loop to flow water
through the boiler and deliver heat to the system loop. The purpose of System / Boiler Loop
piping is to separate or “decouple” the system flow rate from the boiler
flow rate.
The System Loop will have its own dedicated pump flowing at one flow
rate and the separate Boiler Loop will have two dedicated pumps to
flowing into and out of the boiler’s two heat exchangers. The Boiler
pumps are sized based on the head loss of the boiler and related pipe
and fittings in the Boiler Loop only.
Multiple boilers may also be installed with a System / Boiler Loop format
with a manifold system that connects the multiple boilers to the System
Loop. Multiple boilers should be connected to the common manifold in
Reverse / Return to assist in balancing flow to multiple boilers. See
diagram A4 on page 33.
BOILER CIRCULATOR REQUIREMENTS
There will be a minimum of three pumps in a SYNC System / Boiler Loop, one pump for the
System Loop and two pumps for each heat exchanger in the Boiler Loop. All pumps are provided
by the installer. A pump is required on each heat exchanger and must be wired into the boiler
controls. This is required to get maximum efficiency out of each exchanger when fired separately.
In addition to the two pumps, check valves are required to reduce the potential for water
recirculation when only one pump is flowing. Also, Wye Strainers are recommended to remove
particles from the piping system that could damage the boiler’s heat exchanger and cause a non-
warrantable failure. The stainless steel coils inside the heat exchanger are small and can
become clogged if there is loose debris floating in the water piping.
Reference Drawin
g
A1
–
Pa
g
e 30

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Designer’s Guide / SYNC Boiler
The boiler pumps must be sized to provide adequate flow through the boiler and the Boiler Loop
piping. A pressure drop chart is provided to assist in proper pump selection the chart lists the
values for EACH heat exchanger. This table provides GPM and boiler head-loss at various
temperature rises for each model based on Btu/hr input. Pipe diameter and length are critical to
ensure proper flow through the boiler. From the table, choose the temperature rise and the flow
rate for best operation of the boiler.
Wye Strainers
(typical)
Pump 1
Pump 2 To Drain
Check Valves
(Typical)

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Designer’s Guide / SYNC Boiler
Reminder: the flow rates and other values listed on the preceding page are for each heat
exchanger. When combined in common water piping, the flow rates will double. Increase pipe
size accordingly. Use 2-1/2” minimum common manifold pipe size.
ADDITIONAL CIRCULATOR PUMP SPECIFICATIONS
1. Maximum operating pressure for the pump must exceed system operating pressure.
2. Maximum water temperature should not exceed the nameplate rating.
3. Cast iron circulators may be used in closed loop systems.
WATER FLOW
Is the minimum planned flow rate for the system loop below that of the
minimum allowable flow rate through the boiler?
The lowest potential System Loop Flow Rate MUST be ~10% greater than the
Boiler Loop flow rate.
THE BOILER PUMP MUST BE A CONTINUOUS SPEED PUMP THAT KEEPS A CONSTANT FLOW THROUGH
THE BOILER.
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